Radio reception instrument



J. c. LEEPER RADIO RECEPTION INSTRUMENT Filed June 15, 1927 I PatentedOct. 9, 1 928.

UNITED STATES PATENT OFFICE;

JESSE o. LEEPER, or mas MOINES, I'o wA, VASSIGNOR, BY DIRECT AND MESNEASSIGN- MENTS, or FORTY-FIVE onn-nunnnnnrns TOGRAN'I n, BRAYTON AND TENONE- HUNDREDTI-IS TO enaanncn nQ'rowNsAN; BOTH or as MOINES, IOWA.

RADIO RECEPTION INSTRUMENT.

Application filed June 13,1927. Serial No. 198,433.

The object of my invention is to provide what may be termed a vestpocket radio.

Still a further object is to provide a casing having electrc-magnetstherein and having a crystal detector holder formed therein forreceiving a crystal and for retaining a cat whisker in contact with thecrystal together I with a sound reproducingdiaphragm connection withsaid magnets.

Still another obj ect is to divide the casing of the instrument into twocompartments, one for containing the radio reception instruments and theother for retaining a drum whereby a lead wire of considerable lengthmay be wound upon the drum by spring actuation thereof when the deviceis not being used.

Still another object is to arrange one side of the reception circuit sothat when.

the instrument is retained in the hand and held adjacent the ear of theuser, the body of the user serves as an antenna and the body f I p twocompartments A and B;

itself is part of the reception circuit.

Still another object is to provide ametal stamping which receives thecrystal cup'and atthe same time when mounted in position within thecasing serves to ground the crystal which is one side of the receptioncircuit; to the casing so that the hand of the user when holding theinstrument servesto electrically connect the instrument to the body ofthe user. The body of the user therebyserves as a conductor for"conveying the electrical energy from the air to the combined telephoneand detector circuit'in said casing. V

lVith these and other objects in vie'wrmy invention consists in theconstruction, arrangement and combination of the various parts of mydeviceg whereby' the'objects conlated are attained as hereinafter moretemp 7 h p torus pointed out in my nieces;

otherwise supported relative thereto,

I plate 14 by bolts 23.

and illustrated in the accompanying drawings in which: I

Figurel is a perspective view of my radio reception instrument.

Figure 2 is a plan view of the same with the receiver cap and diaphragmremoved.

Figure 3 is a perspective view of a stamping used in my instrument tohold a crystal detector cup.

Figure 4 is a perspective view of another stamping used tohold the catwhisker.

Figure 5 is a sectional view taken on the line 5 f Figure 2 toillustrate the internal construction of my instrument."

Figure 6 is an electrical diagrammatic'al view of my instrument; and

Figure 7 is a detail sectional view taken on th'e'line 77 of Figure 5. I

In one of the embodiments of myinveirtion as shown in the accompanyingdrawing I have used the'reference numeral 10 to indicatethe casing of myreception instru ment. The casing may be formed of suitable electricallyconductive metal preferably non-magnetic,'and is provided with abackmember 12. Positioned adjacent the central portion of the casing 10 is asupporting partition plate 14L The plate 14 is received in a groove 16formed in the casing 10 or The partition plate 14 divides the casing 10into Mounted upon the supporting plate Hand on t-he front side thereofis a pair of permanent magnets 18, the poles of which terminate as at 20adjacent each other The pair I of magnets 18 may be referred to as afront magnet and as a back magnet. The.magnets 18 are thuslocated in thecompartmentA.

The poles 20 of the magnets18 are connected by bridge members 22 tocores 24. The poles 20 and the bridge members 22 are secured togetherand held assembled on the Nuts 25 are positioned on the bolts 23 restingagainst the front surface of the front magnet 18.

Mounted on each core 24 is a pair of spool ends 26 preferably formed ofinsulating material. Betweenjeach pair of spool ends 26 is wound coil offine current conducting ceiving sets.

and is provided detector circuit.

' of the casing is a sound reproducing diaphragm 42. The diaphragm 42held in position by a cap 44. The cap 44 shown in the drawings is oiinsulating material with an opening at center.

The foregoing description discloses a receivermade very similar to oneot' those oil a head set used in connection with radio re The variablecurrent in the coils 28 willvibrate the diaphragm 42 for reproducingsignals imparted to the coils 28 in the form otradio waves.

l A crystal cup holding member 48 is pro-' vided in my instrumentand'consists of astamping having a depressed portion for forming asocket 50 to receive a crystal cup. A crystal cup 52 is adapted to betrictionally held within the socket 50. The crystal cup 52 comprises arectifying crystal 54 embedded in lead or an equivalent sott metal. Theholding member or stamping 48 is provided with an opening 56 adapted toreceive one of the bolts 23. A nut 58 is screwed on to the bolt 23 abovethe stamping 48 for supporting it in position. Another opening 60 isformed in the member 48 and is adapted to receive the terminal bolt 38.A spacer 62 is positioned between the member 48 and the lead 40 on'thebolt 38 and a nut 64 is screwed onto the bolt 38 against the member 48for holding it on the bolt.

From the construction of the parts just described, it will be evidentthat the lead 40 and the crystal cup 52 are connected through the member48 to the bolt 23 which is in contact with the metallic supportingpartition. plate 14. This afifords a connection through the supportingplate 14 to the metallic casing 10,-the metallic casing affording 1 oneterminal for the combined telephone and A cat whisker holding member 66is provided with a downwardly and inwardly extendin'g foot 68. The foot68 is provided with an opening 70 adapted to receive the bolt 36 wherebythe foot 68 is positioned over the lead 40 thereon and may be retainedinthis position by a nut 72. The member 66 is in the form of a metalstamping} The free end of the member 66 is provided with a pair of cars74 adapted to be bent over a cat whisker 76 as illustrated in Figure 2.

Figure 4 shows the cars 74 before being bent over the cat whisker 76.The cat whisker 76 may be securely held in position by drops of solder 78. The treeend of the cat whisker 7 6 is adapted to contact with thecrystal 54.

Secured to the back 12 of the casing 10 and within the compartment B isa stub shaft 80. A sleeve 82 is rotatably mounted on the shaft and has aflange portion 84. A drum head 86 is riveted to the flange 84 of thesleeve 82 and is provided with a drum hub 88. A, second drum head issecured to the drum hub 88. The drum head 90 is made of insulatingmaterial.

A flexible insulated cable 92 is wound on the drum hub 88 between theheads '86 and 90 thereof and has its inner end extending through thedrum head 90 and connected to a rivet 94. The free end of the cable 92extends through an opening 98 in the casing 10 and is connectedpreferably to a ground ing clamp 96. The casing 10 is formed with apocket 100 adjacent the opening 98 to receive a portion of the clamp96.w

. Secured to the terminal bolt 36 is aresilient strip of metal 102extending through an opening 104 in the supporting member 14 affordingthe other or opposite terminal of the combined telephone and detectorcircuit and adapted to rest in contact with the rivet 94 whereby anelectrical connection is made between the terminal bolt 36 and the cable92. This connection continues regardless of the rotation of the drum inthe compartment B Surrounding the sleeve 82 is a' winding spring 106 forthe cable drum. The spring 106 has one end extending through the flange84 of the sleeve 82 and the other end fixed to the stub shaft '80. Thearrangement just described will allow pulling the'clamp 96 from thepocket 100 for unwinding the cable 92 against the tension of the spring106.

To prevent the return of the clamp to the pocket the drum head 86 isprovided with ratchet teeth 108. A pawl 110 is adapted to coact with theteeth 108. The pawl 110 extends through an opening 112 formed in theback 120i the casing 10 and the portion extending through the back canbe depressed as illustrated in dotted lines in Figures 5 and 7 forreleasing the drum and allowing the spring 106 to return the clamp 96 tothe pocket 100. I

It will be noted that my device forms a complete radio reception set andthat it is quite small, convenient and simple to oper-' ate and connectup for operation 1t requiring.

only a single connection to one or the other of the terminals of thecombined receiving and detecting device,

In the actual use of myv invention have observed that the body of theoperator or holder of my radio reception instrument, serves as an aerialwhen the clamp 96 is attached to a ground connection or conductor. I

Some changes may be made in the construc tion and arrangement of theparts of my de vice without departing from the real spirit and purposeof my invention, and it is my intention to cover by my claims, andmodified forms of structure or use ofmechanical equivalents, which maybe reasonably in cluded within their scope.

I claim as my invention:

1. An instrument of the class described, comprising a metallic casingadapted to be in contact with the user of the instrument, a telephonereceiver mounted in said casing, a pair of terminal posts forsaid'receiver, a detector crystal supported on one ofsaid posts and acat-whisker supported on the other of said posts to coact with thecrystal, both of said posts being included in a radi ant energyreceiving circuit, one of which is connected to the metallic casing.

2. An instrument of the class described, comprising a metallic casingadapted to be in contact with the user of the instrument,'a telephonereceiver mounted in said casing, a pair of terminal posts for saidreceiver, a detector crystal supported on one of said posts and acat-whiskersupported on the other one of said posts to coact with thecrystal, one of said posts being connected to said casing, and aflexible conducting cable attached to the other of said posts.

Des Moines, Iowa, June 10, 1927.

JESSE o. LEEPER.

